Merge pull request #71 from atom/as-dont-watch-same-editor

Don't watch editors more than once if they're re-added to the workspace

lib/main.coffee

@@ -2,6 +2,13 @@ WrapGuideElement = require './wrap-guide-element'
 
 module.exports =
   activate: ->
+    watchedEditors = new WeakSet()
+
     atom.workspace.observeTextEditors (editor) ->
+      return if watchedEditors.has(editor)
+
       editorElement = atom.views.getView(editor)
       wrapGuideElement = new WrapGuideElement(editor, editorElement)
+
+      watchedEditors.add(editor)
+      editor.onDidDestroy -> watchedEditors.delete(editor)